Magnetic floor surface

Abstract

The present invention is directed to a method for providing a surface, in particular a floor surface, with a layer of a magnetic and/or magnetizable cover composition, the surface having at least one layer of cementitious material, wherein the method comprises the step of spreading the layer of the cover composition onto the surface, the cover composition comprising a polymeric binder and magnetic and/or magnetizable particles, characterized in that the layer of the cover composition has a water vapor transmission rate of at least 0.25 g h −1 m −2 according to ASTM D1653, and the surface and/or the layer of cementitious material has a relative humidity of more than 75% according to ASTM F 2170-11.

We claim: 
     
       1. A floor surface comprising at least one layer of cementitious material bearing a layer of a cover composition comprising a polymeric binder and magnetic and/or magnetizable particles, the layer of the cover composition having a thickness of 0.15 to 5 mm, and wherein the polymeric binder is prepared from a precursor composition comprising at least a polyisocyanate component and an amine-group containing component, wherein the magnetic and/or magnetizable particles are iron-nickel oxides, ferrosilicones, or combinations thereof, and the layer of the cover composition has a water vapor transmission rate of at least 0.25 g h −1  m −2  and up to 0.711 g h −1  m −2  according to ASTM D1653 test method B, wherein said floor surface further comprises a finish floor covering applied over and fixed by means of magnetic interaction to said layer of said cover composition. 
     
     
       2. The floor surface of  claim 1 , wherein the polymeric binder further comprises a polyol component. 
     
     
       3. The floor surface of  claim 2 , wherein the polymeric binder further comprises one or more catalysts. 
     
     
       4. The floor surface of  claim 1 , wherein the polymeric binder further comprises a material selected from fillers, extenders, pigments or combinations thereof. 
     
     
       5. The floor surface of  claim 1 , wherein the polyisocyanate component has an average NCO-functionality of 1.5 to 4. 
     
     
       6. The floor surface of  claim 5 , wherein the polyisocyanate component comprises a polyisocyanate prepolymer derived from or blended with an uretdione, a biuret or an isocyanurate of hexamethylene di-isocyanate (HDI) or any combination thereof. 
     
     
       7. The floor surface of  claim 6 , wherein the polyisocyanate prepolymer has an isocyanate content of 5-15% by weight. 
     
     
       8. The floor surface of  claim 6 , wherein the polyisocyanate component comprises a polyisocyanate prepolymer derived from an isocyanurate trimer of the HDI, blended with an uretdione of the HDI. 
     
     
       9. The floor surface of  claim 1 , wherein the amine-group containing component comprises a secondary amine. 
     
     
       10. The floor surface of  claim 9 , wherein the secondary amine is an aspartate ester or a composition of the formula (I) 
       
         
           
           
               
               
           
         
         wherein
 X is alkyl, alkylene, aryl or arylene with a valency of n, 
 R 1 , R 2 , R 4  and R 5  are each independently selected from hydrogen, alkyl or aryl, 
 R 3  is alkyl or aryl, 
 n is an integer greater or equal to 1. 
 
       
     
     
       11. The floor surface of  claim 1 , wherein said magnetic and/or magnetizable particles have an average particle diameter from 50 nm to 500 micrometers. 
     
     
       12. The floor surface of  claim 1 , wherein said composition comprises 25 to 50 wt % of said polymeric binder, from 50 to 75 wt % of said magnetic and/or magnetizable particles. 
     
     
       13. The floor surface of  claim 1 , wherein the magnetic and/or magnetizable particles comprise ferrosilicones. 
     
     
       14. A floor surface comprising at least one layer of cementitious material bearing a layer of a cover composition comprising a polymeric binder and magnetic and/or magnetizable particles, the layer of the cover composition having a thickness of 0.15 to 5 mm, and wherein the polymeric binder is prepared from a precursor composition comprising at least a polyisocyanate component and an amine-group containing component, wherein the magnetic and/or magnetizable particles are iron-nickel oxides, and the layer of the cover composition has a water vapor transmission rate of at least 0.25 g h −1  m −2  and up to 0.711 g h −1  m −2  according to ASTM D1653 test method B, wherein said floor surface further comprises a finish floor covering applied over and fixed by means of magnetic interaction to said layer of said cover composition. 
     
     
       15. The floor surface of  claim 14 , wherein said magnetic and/or magnetizable particles have an average particle diameter from 50 nm to 500 micrometers. 
     
     
       16. The floor surface of  claim 14 , wherein said composition comprises 25 to 50 wt % of said polymeric binder, from 50 to 75 wt % of said magnetic and/or magnetizable particles.